This invention relates to a device for introducing a long, thin and flexible medical device, such as a catheter, into a patient's vasculature. More particularly, this invention relates to an improved catheter introducer that facilitates insertion of the catheter introducer into a patient's vasculature and that allows easy insertion of a catheter through the catheter introducer and into the patient's vasculature.
Catheter introducers are typically used in conjunction with peripherally inserted central catheters (PICC), or other relatively long, thin and flexible medical devices, to facilitate insertion and placement of the catheter or other medical device into the patient's vasculature. Current catheter introducers include a splittable cannula and a hub with a pair of wings fixed to the proximal end of the cannula. In addition, such a catheter introducer includes an introducer needle that is disposed in the splittable cannula with the sharp distal tip of the needle extending distally of the distal end of the splittable cannula and with the needle hub extending proximal of the wings and hub on the cannula. As used herein, the term "proximal" refers to a location on the device closest to the clinician using the device. Conversely, the term "distal" refers to a location on the device farthest from the clinician and closest to the patient into whom the device is to be inserted.
When using a typical catheter introducer, the clinician grasps the needle hub so the needle bevel is facing away from the patient's skin and proceeds to insert the distal portion of the needle and cannula at the desired site in the patient's skin. The clinician continues to advance the device until venipuncture has been confirmed. This confirmation is usually done visually when the clinician sees blood entering a flashback chamber formed in the needle hub at the proximal end of the needle. After venipuncture has been confirmed, the clinician advances the cannula distally into the patient's vein and the needle is withdrawn. With the catheter introducer properly placed, the clinician can then insert the PICC, or other relatively long, thin and flexible medical device, into the proximal opening of the cannula and continue to advance the catheter through the catheter introducer until the catheter is properly placed in the patient's vasculature. Alternatively, the introducer needle can be first placed into the patient's vasculature without the catheter introducer. A guidewire is then inserted through the introducer needle into the patient's vasculature. The introducer needle is then removed leaving the guidewire in place to provide a track or guide for the catheter introducer, and dilator if used, to follow into the patient's vasculature. A catheter is then inserted into the catheter introducer over the guidewire. This greatly facilitates the placement of a PICC into a patient's vasculature. After placement of the PICC, the clinician grasps the wings and pulls them apart to split the splittable introducer. In this way, the splittable introducer can be removed from the patient over any hub located on the proximal end of the PICC.
Although currently available catheter introducers generally work in accordance with their intended purpose, they could be improved. For example, when the catheter introducer is inserted into the patient, the hub is adjacent to the patient's skin and blood flows out of the open proximal end of the splittable cannula. This makes it difficult for the clinician to line up the distal end of the catheter with the open proximal end of the splittable cannula. This is especially problematic since the clinician must always approach the open proximal end of the splittable cannula with the distal end of the catheter along the longitudinal axis of the splittable cannula and since the outer diameter of the catheter is only slightly smaller than the inner diameter of the splittable cannula. In addition, the location and configuration of the wings on the splittable cannula require a certain minimum insertion angle for the device that in some cases may be too large.